Marc Spector has led an interesting life. First a marine, then a CIA agent, and finally a mercenary. Left for dead in the desert, he found himself looking up at a statue of the Egyptian god Khonshu who he credits with saving his life. Spector returned to New York to become a hero under the name Moon Knight.
His marine and CIA training alongside his intermittent supernatural powers from Khonshu make him a formidable opponent. Unfortunately, he also suffers from a variety of mental health issues, including depression and multiple identity disorder which can put him at a disadvantage. There are few DC villains who would be willing to exploit that.
10 BEAT: Two-Face
When Harvey Dent first became part of the Batman world, he was an ally. The District Attorney of Gotham City waged his own war on crime until that was disrupted by a mob boss's attack on him. The event left Harvey twisted and scarred, both inside and out, with a new life as the villain Two-Face. If Moon Knight found himself in Gotham, he would almost certainly fight Two-Face. He's constantly trying to take over the criminal underworld in Gotham, which would absolutely put him in Moon Knight's line of sight. If Two-Face can't handle Batman, he certainly cannot handle Moon Knight.
9 DESTROYED BY: Ra's al Ghul
One the most Machiavellian individuals in DC, Ra's would draw Moon Knight's attention almost immediately. The virtually immortal leader of the League of Assassins has spent multiple lifetimes manipulating world events either through subterfuge or by force. His repeated attempts to draw Batman into his plans have failed, but he might find more success with Moon Knight.
Ra's would find his multiple personality issues an easy way to manipulate Spector into working for his cause. If Moon Knight chose to oppose Ra's, its unlikely that he could stand against his forces.
8 BEAT: The Riddler
Obsessed with proving he's smarter than Batman, The Riddler has spent his criminal career trying to be one step ahead of the Caped Crusader, but typically ends up one step behind him. The problem with Moon Knight is that his indulgence in Riddlers games would only go so far before he kicked the pieces off the board. Rather than trying to solve the riddles, it's more likely that Moon Knight would smash his way through the traps and beat Riddler within an inch of his life. He simply wouldn't be as tolerant of Riddler's shenanigans as Batman has been.
7 DESTROYED BY: Deathstroke
DC's most prominent and effective mercenary has fought teams of superheroes to a standstill. Deathstroke is well trained, highly experienced, and ready for virtually any eventuality. The same can be said of Moon Knight, but the difference between the two is a matter of focus.
Deathstroke's single minded attention to his mission, whatever it may be, often gives him an edge over most of his opponents. He doesn't stop until the job is done. Moon Knight, on the other hand, is far more unfocused, which is something that would inevitably give Deathstroke the win.
6 BEAT: Bane
Given Bane's size and strength advantage, it would be easy to assume that he would defeat Moon Knight, but that's not the case. Moon Knight's combat training combined with his enhanced strength and durability would help him stand toe to toe with the Venom powered villain. Bane's also not smart enough to manipulate Moon Knight's weaknesses, so that won't be an issue for Spector. But Moon Knight's biggest advantage is Bane's arrogance. Because he's bigger and and stronger, Bane would assume victory and operate accordingly. Moon Knight would take advantage and find a way to win.
5 DESTROYED BY: Prometheus
In his DC debut, Prometheus dismantled the Justice League one piece at a time and almost carved out a victory against them. Had it not been for some unexpected allies aiding the Justice League, he would have done just that. Prometheus is brilliant, in possession of exotic technology, and is meticulous in his planning. You ever know what angle he would come from.
The unfortunate reality for Moon Knight is that Prometheus can beat him physically and mentally, possibly before the fight has even started. Moon Knight simply isn't ready for a villain the caliber of Prometheus.
4 BEAT: Captain Cold
Part of Flash's rogues gallery, Captain Cold has fought more than one iteration of the Scarlet Speedster and almost won. He is more than a man with a freeze gun. He's a superb strategist that develops plans that put him at the advantage, no matter who he's facing. Moon Knight is an entirely different problem. The problem Cold faces with Moon Knight is that he can be quite erratic and unpredictable. He doesn't operate the same way most heroes would, making it hard for Captain Cold to plan for him. After that, it wouldn't be difficult for Moon Knight to overcome the freeze gun and take Cold down.
3 DESTROYED BY: Deadshot
When Floyd Lawton takes a shot, he doesn't miss. That's how you earn a name like Deadshot. An expert marksman on another level, Deadshot isn't the most powerful villain in DC but he's definitely the most accurate. While Moon Knight could probably take him in a fight, it's unlikely Deadshot would let it get that far.
He would take Moon Knight out from a distance before Spector even knew Lawton was there. Moon Knight might have some superhuman abilities, but he certainly isn't bullet proof. The big thing in his favor is that Lawton doesn't normally kill people he hasn't been paid to.
2 BEAT: Captain Boomerang
This one would actually be a good fight. Captain Boomerang is known for the expert way he wields his arsenal of unique boomerangs, as well as his impressive blood lust. That's led him to being one of DC's most dangerous villains. Moon Knight is a better overall fighter, so Captain Boomerang would need the element of surprise combined with his non traditional weaponry to stand a chance. His attacks would catch Moon Knight off guard. Well, at first. Once Moon Knight gauges his abilities, he would be able to take the advantage back and win the fight.
1 DESTROYED BY: Joker
Joker isn't the strongest villain. Or the best fighter. Or even the smartest. What he has over Moon Knight is his psychotic charisma. Joker has spent a lifetime plaguing Batman and other DC heroes with his insanely unpredictable and frequently poorly thought out plans. The goals of said plans often make no sense to anyone but him. Moon Knight would be his play thing simply because he lacks the mental fortitude to fend the Joker off. More than being physically crushed by him, Moon Knight would lose the battle mentally. Joker might even get the one thing from Moon Knight he's always wanted from Batman: a friend.